A technique for isotope separation, particularly for uranium U.sub.235 enrichment, operates by selectively photoionizing particles of one isotope type, typically U.sub.235, in an environment of plural isotope types including, for example, U.sub.238, and by subsequently applying a crossed-field magnetohydrodynamic force to the selectively photoionized particles in order to accelerate them onto trajectories which carry them to collection surfaces where they are deposited. The crossed-field forces result from simultaneous application of orthogonal magnetic and electric fields. A typical example is shown in United States patent application Ser. No. 25,605, filed Mar. 25, 1970, and incorporated herein by reference.
An object of the present invention is to apply acceleration forces for the selectively ionized particles without the direct generation of magnetohydrodynamic forces.